J-20... The New Generation Fighter II

Bltizo said:

^ Very informative and interesting, but doesn't really answer my question.

I'll put it another way (not demanding you answer it of course, just disputing a point that asymptote made a few pages back).
Let's say the trailing edge of the J-20s canard were aligned with the main wing's trailing edge on the same side. Does that produce a massively different radar return than if the trailing edge were aligned diagonally?

^ Red line shows current "diagonal" alignment, blue lines show the a hypothetical modified canard with a trailing edge which aligns on the same side with the wing behind it rather than the wing opposite/behind it as is the J-20's current "diagonal" case.

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It probably does. The Korean stealth project "KFX" is design just like above - they probably think its better to align it on the same side than diagonally.

Korean KFX


Remember, there is the main aircraft body in middle so aligning diagonally seems pointless if the other side get shielded by the main airframe body. So its better and more logical to just align on the same side, when the radar wave hits from one direction (let's say 45 degree off the aircraft) all the edges from one side will be aligned.

airsuperiority said:

By his "logic", since Chinese developed firearms, then anything the West made, should always be inferior to China. And he said Chinese thought they had better firearms weapon? Seems like he's the know-it-all of the entire Chinese civilization and stealth technology. We better not disagree with him because he's always right, and he can disprove us with blow-up dolls

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Hey if you don't like what I say, you can always press the ignore button.

The truth is you know I am right because I touched a nerve and you seem to be persistent reply to me or talk about me.

Bltizo said:

I see... so we can not definitively say which trailing edge configuration would produce a lower return, right?

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Correct...But the more scattering points you have, the greater the odds of an RCS that you may not like. That is why the F-117 retract its comm antennas prior to hostile airspace. Gaps on the gear doors are inevitable and they are scattering points, so we saw-tooth those gaps to deflect any reflected signals away from the transmitter's direction. A pylon has many scattering points, so we eliminate pylons. The list of scattering points is enormous.

gambit said:

Correct...But the more scattering points you have, the greater the odds of an RCS that you may not like. That is why the F-117 retract its comm antennas prior to hostile airspace. Gaps on the gear doors are inevitable and they are scattering points, so we saw-tooth those gaps to deflect any reflected signals away from the transmitter's direction. A pylon has many scattering points, so we eliminate pylons. The list of scattering points is enormous.

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Sweet thanks a lot

tanlixiang28776 said:

I can accept it if its based on factual assertion. Asymptote is not an aerospace engineer, or even engineer at that. He also quotes posts from other sites to try to prove his point which are also not based on fact. His entire argument is that China is new and is inferior.

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Yeh? well, I have read many MANY defence forums and analysis on J-20, and most of them are not even remotely professional in their discussion about J-20. quellish's analysis on J-20 strikes me as being fairly professional, because he has citation to back up his material, and his discussion is grounded in real science that's why I quoted him. Compare to something like most pro-China forum posters here who seem to believe J-20 is as good as or better than F-22 because "the magical canard is made of 10000% radar absorbent material" or J-20's RAM paint can absorb EVERY RADAR FREQUENCY CONCEIVABLE. Its ridicules to even believe that. And most people here seem to believe that. Radars have specific bands it operates in. But most people here seem to believe all radar frequency operates in same band/frequency, so as long as we apply heaps of these "magic RAM paint" at whatever places J-20 is having stealth problem, it will ALL GO AWAY.

supercat said:

The problem with Asymptote's argument is that it is too simplistic. I doubt you can tell which one is more stealthy by just eyeballing it, except for the nozzles. If this is the case, I would say F-22 negates all its advantages in geometry by having such huge vertical tails. The Americans have run their numbers through supercomputers, so have the Chinese.

U.S. and China are the only countries which successfully tested mid-course interceptions, and China did it only in last year. This demonstrates two points: new is not necessary inferior, and Chinese ASBM is not that inconceivable considering Chinese can employ similar technologies from their experience with mid-course interception.

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Jesus, are you guys still using the same "China is got mid-core interception SC-19 so everything China does is better than anyone in the world" argument. That's exactly the "" that latentlazy mentioned before.

victtodd said:

The thread runs the risk of being ruined by trolls, so many pages, so little substance. When the guy repeatedly brought up boxer rebellion, you guys should realize it is a troll. So for the love of God, stop feeding it!

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What? you don't believe Boxer rebellion is real?
I am merely pointing out many forum poster's attitude here are like those boxers who believes they are Kungfu masters and their Kungfu made them "invincible", "stops bullet and canon", only to be obliterated by the real canon.

I find it even more absurd majority here believes China's J-20 is already superior to PAK FA.
Let's put it this way, in the history of aviation in China, which combat aircraft China design and produce themselve, (or any combat aircraft subsystems China produced), is superior to Russian's?

No, don't bring up that "SC-19 mid-cource ASAT interceptor", or "Chinese economy is world's second largest", or the "super computers", or the "Three Gorges Dam"(!? believe or not I have seen people use this as counter argument...LOL).....
We are talking about aircraft here.

Seriously, so far China has nothing that's even comparable to the Russian in the same class and yet majority here seems to believe China is already better than Russian, and even US tech. Its laughable and sad.

Bltizo said:

^ Very informative and interesting, but doesn't really answer my question.

I'll put it another way (not demanding you answer it of course, just disputing a point that asymptote made a few pages back).
Let's say the trailing edge of the J-20s canard were aligned with the main wing's trailing edge on the same side. Does that produce a massively different radar return than if the trailing edge were aligned diagonally?

^ Red line shows current "diagonal" alignment, blue lines show the a hypothetical modified canard with a trailing edge which aligns on the same side with the wing behind it rather than the wing opposite/behind it as is the J-20's current "diagonal" case.

Click to expand...

Remember, there is the main aircraft body in the middle (the fuselage) so aligning diagonally seems pointless if the other side get shielded by the main airframe body. So its better and more logical to just align on the same side, when the radar wave hits from one direction (let's say 45 degree off the aircraft) all the edges from one side will be aligned.

Bltizo wrote:
I don't think they're contrails, I heard someone on another forum saying the J-20 was dumping fuel.

It is safer to dump fuel from the tip of a wing than through the jet pipes.